Malicious PDF — malware analysis report

Static analysis result for SHA-256 d905fe28cd4a6489…

MALICIOUS

PDF

71.9 KB Created: 2021-10-01 03:36:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 72d753c121aa21c2c418c0a5219bf45b SHA-1: 624b3469e4fd13900aae4251ea3fe85c0c1dc435 SHA-256: d905fe28cd4a648939cf4177f5d635abb8237b94e11866fe4aaf91f6bc4c7249
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm pointing to multiple compromised websites, likely intended to trick users into downloading malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.ks-klinika.ru/ckfinder/userfiles/files/vewemomenided.pdf In PDF document text
    • http://cellesekorea.com/ckupload/files/632769040.pdfIn PDF document text
    • http://gadkowski.pl/repository/filemanager/file/69880106180.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/f97tf5pvqbsa2tmcmcb8gv5626/83899714533.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/d55392e18fcd7e0219f8dfdb7ed68e1d/busupej.pdfIn PDF document text
    • http://pro-elec.ru/ckfinder/userfiles/files/81918446544.pdfIn PDF document text
    • http://briquettemachinery.com/d/files/39809618164.pdfIn PDF document text
    • http://peoplefoster.com/pliki/69373686000.pdfIn PDF document text
    • https://ietc-oman.com/userfiles/files/kupododebib.pdfIn PDF document text
    • http://ikhmongol.mn/ckfinder/userfiles/files/41727792494.pdfIn PDF document text
    • http://3colorjazz.com/fckeditor/userfiles/image/sujuw.pdfIn PDF document text
    • http://langmypham.com/luutru/files/15893681548.pdfIn PDF document text
    • http://perfekt-dom.pl/designhome/admin/userfiles/file/85573250312.pdfIn PDF document text
    • http://jiin-torng.com/uploadfiles/20210909081442.pdfIn PDF document text
    • http://www.praasia.com/file/files/nuxibobuvipazi.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/20e3b55359288a653363599a1b2219c5/kudowosuzod.pdfIn PDF document text
    • https://krygina40.ru/UserFiles/File/kulor.pdfIn PDF document text
    • https://resttour.com/images/userfiles/files/tiwilisiteramawuraw.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614ee4222bdaa---mebekexam.pdfIn PDF document text
    • https://manpowernepal.net/ckfinder/userfiles/files/33899924369.pdfIn PDF document text
    • http://khiensa.com/UserFiles/File/didanol.pdfIn PDF document text
    • http://davcpundri.com/css/file/50357345801.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614451b690e49---pitusamizevejirebep.pdfIn PDF document text
    • http://buffagiuseppeinfissi.com/userfiles/files/22619612201.pdfIn PDF document text
    • https://pnp-studio.com/fckeditorfiles/file/tefufapu.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/dna0q5g6d7rga3ukm44bdm82gc/71868588127.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=door+lock+software+downloadPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b59d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB59D 10556 bytes
SHA-256: 18d5bf5062eab469aea7dad18b88a5b460a7d47bcda0c0b2ae03aa6c915e7155
font_01_sfnt_off0000cde7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDE7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e5f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F9 16904 bytes
SHA-256: 4a2840a1e9f0d8fc7b132cf50db374aefd2ab7a6da36305fdfbbbe03f71096ad